Ultra is one of the world’s leading providers of sonobuoys, with its products spanning the entire spectrum of types and sizes. Ultra’s sonobuoy development is currently primarily focused on improving multistatic ASW operations, which require the employment of passive and active sonobuoys, as well as significant signal processing. This is driven by the increasing threat from modern, quiet submarines, which have become difficult to detect using conventional ASW techniques.

Ultra is leading work, with key government and industry partners, to develop a miniaturised sonobuoy system. The aim is to develop a series of sonobuoys optimised for carriage and deployment from unmanned air vehicles (UAVs), bringing these potent long endurance platforms successfully into the ASW force mix.

This work encompasses the broader system including the sonobuoys, the sonobuoy carriage system, sonobuoy receivers and the wider comms network. This exploits the Group’s leading capabilities in network communications and tactical data links such that the UAV, and the sonobuoys it has deployed, can contribute to the integrated sonar system and the ASW mission.

Ultra has over 5000 receivers installed around the world, supporting a variety of helicopters, maritime patrol aircraft (MPA), surface combatants and laboratories. Ultra continually builds upon its experience gained with existing systems, new developments and technology advances, to push performance and function envelopes for these highly sophisticated advanced receivers, while reducing the cost per channel. The latest sonobuoy receivers are software-defined wideband solutions, which receive signals over long ranges and with very low distortion. The flexibility of the systems allows customers to vary data rates, enabling a greater flow of information in today’s increasingly multistatic ASW operations. Ultra’s systems save the customer weight and power, – important considerations for airborne platforms – and they are compatible with outputs from area networks.

Ultra’s products range from very lightweight helicopter/MPA sonobuoy receivers, to the wideband software-defined receiver, which offers the ultimate in flexibility and performance. This has the ability to manage the RF spectrum dynamically, to find and amplify the signals of interest and remove interference.

Ultra’s MSA enhances the detection of quiet submarines, in both deep and littoral waters, by using a field of active and passive sonobuoys, controlled and monitored by an airborne processing suite. It uses multiple sources and receivers, positioned in different locations, so that echoes from active sources are picked up by a pattern of receivers, which take advantage of multiple returns from the submarine at multiple aspects. These multistatic combinations of sonobuoys are collectively exploited to produce an accurate target track.

This functionality is now included in Ultra’s compact and lightweight airborne acoustics package offerings, which meet the needs of both current and future fixed-wing MPAs.